Directories

DEX: Yellow Pages

DEX: White Pages

Switchboard

Area Codes and Zip Codes

National Address Server

USPS Zip Code Lookup and Address Information

Associations and Societies

Internet Public Library
A collection of over 1100 Internet sites providing information about a wide variety of professional and trade associations, cultural and art organizations, political parties and advocacy groups, labor unions, academic societies, and research institutions.

Guidestar
A guide to over 40,000 American non-profit organizations.

Scholarly Societies Project
A directory of over 1100 professional societies in the United States. The list can be browsed alphabetically or by any of 39 subjects.

Publishers

Publist.com
A centralized source of information on more than 150,000 of the world's periodicals. Its data comes from authoritative sources, like R.R. Bowker's Ulrich's International Periodicals Directory and Editor & Publisher International Yearbook.